Methods and system for efficient self-coexistence of wireless regional area networks

Abstract

A method for scheduling self coexistence windows (SCWs), wherein SCWs are part of frames transmitted in wireless regional area networks sharing a common channel, comprises monitoring the common channel for a duration of at least a maximum SCW cycle length; checking if at least one coexistence beacon protocol packet including at least one of SCWs and quiet periods scheduled by neighbor WRANs is detected on the common channel; and establishing a SCW schedule by setting SCW schedule fields in a modified superframe control header, wherein the newly established SCW schedule does not conflict with any already scheduled SCWs and quiet periods.

The invention claimed is: 
     
       1. A method for scheduling self coexistence windows (SCWs), wherein SCWs are part of frames transmitted in wireless regional area networks (WRANs) sharing a common channel, the method comprising:
 monitoring the common channel for a duration of at least a maximum SCW cycle length; 
 checking if at least one coexistence beacon protocol (CBP) packet including at least one of SCWs and quiet periods (QPs) scheduled by neighbor WRANs is detected on the common channel; and 
 establishing an SCW schedule by setting SCW schedule fields in a modified superframe control header (SCH), the SCW schedule fields comprising an SCW cycle length field that indicates a number of superframes to be transmitted between each superframe carrying an SCW. 
 
     
     
       2. The method of  claim 1 , further comprising conveying a reservation-based SCW schedule to neighbor WRANs. 
     
     
       3. The method of  claim 2 , further comprising adjusting the reservation-based SCW schedule by updating values of the mode field. 
     
     
       4. The method of  claim 1 , wherein the SCW schedule fields further comprise an SCW Cycle Offset field, and an SCW Cycle Frame Bitmap field. 
     
     
       5. The method of  claim 4 , wherein the self coexistence windows (SCWs) are reservation-based SCWs. 
     
     
       6. The method of  claim 5 , wherein setting the SCW schedule fields further comprises setting a value of the SCW Cycle Offset field to a number of superframes greater than a number of superframes assigned in the SCW Cycle Length field; and setting every 2 bits in the SCW Cycle Frame Bitmap field corresponding to a frame to be reserved to a value indicating a reservation-based SCW. 
     
     
       7. The method of  claim 6 , wherein an owner WRAN has exclusive access to reservation-based SCWs indicated in the SCW schedule. 
     
     
       8. The method of  claim 4 , wherein the self coexistence windows (SCWs) are contention-based SCWs. 
     
     
       9. The method of  claim 8 , wherein setting the SCW fields further comprises:
 setting a value of the SCW Cycle Offset field to a number of superframes greater than a number of superframes assigned in the SCW Cycle Length field; and 
 setting every 2 bits in the SCW Cycle Frame Bitmap field corresponding to a frame to be scheduled to a value indicating a contention-based SCW. 
 
     
     
       10. The method of  claim 9 , wherein an owner WRAN shares contention-based SCWs with its neighbor WRANs. 
     
     
       11. The method of  claim 10 , wherein each neighbor WRAN can transmit CBP packets in contention-based SCWs after waiting a random backoff time. 
     
     
       12. A wireless device, comprising:
 a signal sensing module configured to identify co-existing beacon protocol (CBP) packets transmitted on a common channel; 
 a scheduler configured to analyze the CBP packets to determine if self-coexistence windows (SCWs) or quiet periods (QPs) can be scheduled and to schedule at least one of contention-based SCWs, reservation-based SCWs, and intra-frame QPs, the scheduler being further configured to schedule the contention-based SCWs or reservation based SCWs by adjusting SCW schedule fields in a superframe control header, the SCW schedule fields further comprising an SCW cycle length field that indicates a number of superframes to be transmitted between each superframe carrying an SCW; 
 a signal transceiver; and 
 a spectrum manager for managing the common channel and controlling the transceiver to transmit CBP packets in scheduled SCWs or to halt any transmission during QPs. 
 
     
     
       13. The wireless device of  claim 12 , wherein to adjust the SCW schedule fields the scheduler is configured to:
 set a value of an SCW Cycle Offset field to a number of superframes greater than a number of superframes assigned in an SCW Cycle Length field; and 
 set every 2 bits in an SCW Cycle Frame Bitmap field corresponding to a frame to be reserved to a value indicating a reservation-based SCW.